Grinding and polishing tool for cylindrical members



F. L. SCHULZE 2,994,163 GRINDING AND POLISHING TOOL FOR CYLINDRICAL MEMBERS Aug. 1, 1961 2 Sheets-Sheet 1 Filed Sept. 14, 1959 m m m m FREDERICK L. SCH U LZE ATTOP/VEY F. L. SCHULZE 2,994,163 GRINDING AND POLISHING TOOL FOR CYLINDRICAL MEMBERS Aug, 1, 1961 2 Sheets-Sheet 2 Filed Sept. 14, 1959 INVENTOR. FREDERICK L. "SCHULZE Y ATTORNEY Ilnited Stats Fatent 2,994,163 GRINDING AND POLISHING TOOL FOR CYLINDRICAL MEMBERS Frederick L. Schulze, 469 Bogert Road, River Edge, NJ. Filed Sept. 14, 1959, Ser. No. 839,804 3 Claims. (Cl. '51--73) This invention relates to the art of grinding and polishing machines and more particularly concerns a portable device for grinding and polishing cylindrical pipes, rods, tubes and the like.

According to the invention there is provided a tool adapted to grind and polish by abrasion outside surfaces of cylindrical members. The tool may be used to abrade end portions of cylindrical members or the entire outside cylindrical surfaces. The device includes counterweighted assemblies having pivotally mounted abrasive members which are pressed by centrifugal force against a cylindrical member being treated in the tool when the tool is rotated on the member. The member being treated may be made of metal, wood, plastic or other material.

It is therefore a principal object of the invention to provide a portable tool adapted for fitting on the body of a cylindrical member and rotated thereon for grinding and polishing the member.

It is another object to provide a grinding and polishing tool having abrasive members pivotally mounted and counterweighted so that the abrasive members are pressed inwardly against the work when the tool rotates, the pressure being applied counter to centrifugal force tending to drive the counterweights outwardly.

A further object is to provide a tool of the character described which is easily assembled and disassembled for replacement and adjustment of abrasive members and other parts.

A still further object is to provide a tool of the character described adapted for being directly motor driven or driven via belt or gear drives.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

FIG. 1 is a longitudinal sectional view of a tool embodying the invention.

FIGS. 2, 3 and 6 are sectional views taken on lines 2-2, 33 and 66, respectively, of FIG. 1.

FIGS. 4 and 5 are opposite end elevational views taken on lines 44 and 55, respectively, of FIG. 1.

FIG. 7 is a perspective view of an abrasive member employed in the tool.

FIG. 8 is a perspective view of another tool embodying the invention.

Referring to FIGS. l6, there is shown a tool T including a cylindrical casing 10 having circular end or face plates 12 and 14 secured at opposite ends of the casing to form a substantially closed cylindrical body. Secured to end plate 12 by nuts 16 and 18 is an axially disposed spindle 20. This spindle may be attached to a motor drive shaft by a chuck or other suitable coupling means for rotating the tool. The end or face plates 12, 14 are secured to the casing by three bolts 21 and nuts 24, 25 at opposite ends. A pair of annular plates 26, 28 are secured to the face plates 12, 14 by nuts 30, 31 and 32, 33 engaged near opposite ends of the bolts 21. Plates 26, 28 have central apertures 35, 36.

Face plate 14 has a cylindrical neck extension 38 ice adapted to receive a cylindrical bushing 40 of any de"-* sired internal diameter depending on the external diameter of a cylindrical member M to be ground and polished by the tool. The member is shown by dotted lines in FIG. 3. The bushing has an end flange 41 which seats on the outer free end of neck 38. A thumb screw 42 is carried in a threaded hole 39 in neck 38 for removably retaining the bushing therein.

Plates 26, 28 carry three counterweighted abrasive assemblies 50. Each assembly includes a heavy cylindrical weight 52 having axial pintles 54 engaged in holes in a pair of counterlevers 56, 57 disposed perpendicular thereto and spaced from the plates 26, 28. The counterlevers are supported by a stationary shaft 58 having a head 60 abutting plate 28 and disposed between plates 28 and 14. The shaft 58 passes through holes in plates 26, 28 and has a free end extending into the space S between plates 26 and 12. The counterlevers are generally triangular in form. The shaft 58 passes through the counterlevers near the apices thereof as shown in FIGS. 2 and 3. Weight '52 is located at the ends of longer edges 53 of the counterlevers. At the ends of shorter edges 55 of the counterlevers is mounted a cylindrical abrasive member 62. This member, as best shown in FIG. 7, has a hexagonal shaft 64 terminating in axially extending threaded ends 66.

The ends of shaft 64 extend slightly beyond the circular ends of the abrasive member 62 and seat in hexagonal holes in the counterlevers. By this arrangement the abrasive member can be removed from the counterlevers, rotated and reseated in a diiferent position to equalize wear on the member. Nuts 68 and 69 are threaded on the screw ends 66 of the shaft for removably securing the abrasive member 62 to the counterlevers. Coil springs 70 and 72 are mounted on opposite end port-ions of shaft 58 between the counterlevers and plates 26, 28. One end of spring 70 is engaged on one of bolts 2123 under a nut 31 at plate 28 and the other end of the spring rests on the nut 68. The other spring 72 has one end coiled around one of bolts 21 and is held by one of nuts 32 at plate 28. The other end of spring 72 rests on nut 69. The springs are coiled and tensioned so that they tend to move the weight 52 inwardly toward the axis of the casing and tend to move the abrasive members 62 outwardly. A stop pin or screw 74 secured by a nut 75 on plate 28 limits this outward pivotal movement of the abrasive assemblies by abutment on an edge 55 of each counterlever 57. A bolt 73 extends between each pair of counterlevers 56 and 57 and is secured by a nut 71.

By this arrangement of the abrasive assemblies, there is provided a clear central or axial passage through the casing from neck 38 to end plate 12. A cylindrical member M of any desired diameter to be ground may be inserted through the bushing 40 as far as plate 12. If a motor is suitably coupled to spindle 20, the tool will be rotated in its entirety on the member M. The tool will be journaled on bushing 40 which will serve as a sleeve bearing. As the cylindrical tool rotates, Weights 52 will move outwardly as indicated by arrows A in FIG. 3 to the outer dotted line position while the abrasive members 62 will move inwardly as indicated by arrows B to the inner position against the tension in springs 70, 72 to contact the outer surface of the end of member M being ground. Since the several abrasive assemblies 50 are independently mounted to pivot on their respective shafts 58, each abrasive member automatically adjusts to the position of the surface of the cylindrical member being ground. The cylindrical member will be ground or polished depending on the grit size of the abrasive employed.

The tool is shown completely assembled in FIGS. 1-6.

The abrasive members can be quickly removed when necessary to reposition them or to change them for others having different grit size. This is done by unscrewing the end nuts 24 from bolts 2123 to remove end plate 12. The spindle 20 comes off with plate 12. Then nuts 30 are unscrewed from bolts 21 to release inner plate 26. The free ends of shafts 58 slide out of the apertures in plate 26 through which they extend. This exposes the counterlevers 56. Nuts 68 and '71 may then be imscrewed to release the counterlevers which may be retracted on the free ends of shafts 58 to expose the abrasive members. Nuts 69 may then be loosened from the screw ends 66 to free the abrasive members. The entire operation of disassembly and assembly can be done very rapidly and requires only a nut wrench.

In the form of the invention shown in FIG. 8, the tool structure T is the same as previously described except that end plate 12 has been replaced by a plate 14 similar in structure to plate 14. This plate 14* has a neck extension 33* adapted to receive another bushing 40 A pulley 80 is secured on the neck extension and may be engaged by a belt 82, which is driven by a motor not shown) to rotate the tool upon the cylindrical member M. The member M is fixed against rotation and sup ports the tool T which rotates thereon, being journaled on bushings 4t) and 40 The member M extends axially entirely through the tool T which can be positioned at any desired location along the member for grinding and polishing. The tool T can be disassembled and assembled in the same facile manner as described above.

The tools described are rugged in construction for heavy duty use. All wearing parts are readily replaceable at small cost. The tools are economical to manufacture, and easy to use.

While I have illustrated and described the preferred embodiments of my invention, it is to be understood that I do not limit myself to the precise constructions herein disclosed and that various changes and modifications may be made within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent 1. An abrading tool for a cylindrical member, comprising a cylindrical body adapted to receive said member in axial alignment therewith, a pair of end plates carried by said body, a plurality of abrasive assemblies pivotally carried by said end plates and pivotable on axes parallel to the axis of said body, each of said assemblies including a pair of spaced supports, a weight and an abrasive element secured to said supports in spaced parallel disposition and spaced from the axis of pivoting of the assembly, and means for rotating said body on said member, whereby said weights are forced centrifugally radially outward of the axis of said body while said abrasive elements are forced radially inwardly toward the axis of said body to abrade said member, said means including a pair of axial neck extensions of said body, said end plates and extensions being apertured so that said member can extend entirely through said body, said body being journaled on said extensions in rotation on said member.

2. An abrading tool for a cylindrical member, comprising a cylindrical body adapted to receive said member in axial alignment therewith, a pair of end plates carried by said body, a plurality of abrasive assemblies pivotally carried by said end plates and pivotable on axes parallel to the axis of said body, each of said assemblies including a pair of spaced supports, a weight and an abrasive element secured to said supports in spaced parallel disposition and spaced from the axis of pivoting of the assembly, and means for rotating said body on said member, whereby said weights are forced centrifugally radially outward of the axis of said body while said abrasive elements are forced radially inwardly toward the axis of said body to abrade said member, said means including a pair of axial neck extensions of said body, said end plates and extensions being apertured so that said member can extend entirely through said body, said body being journaled on said extensions in rotation on said member, and drive means mounted on at least one of said extensions for coupling the body to a motor for rotationally driving the body.

3. An abrading tool for a cylindrical member, CD111 prising a cylindrical casing having circular end plates secured thereto, one of said plates having a neck extension for receiving a cylindrical bushing, an annular plate secured in said casing adjacent to said one plate, said annular plate being apertured so that said member may be inserted through said neck extension and aperture in axial registration with the casing, means associated with the other end plate for rotating the casing on said member, another annular plate disposed in said casing and spaced from said other end plate, and a plurality of abrasive assemblies pivotally mounted on shafts engaged in said am nular plates, each of said assemblies including a pair of spaced supports, a weight and an abrasive element removably secured to said supports, said shafts being disposed parallel to the axis of said casing, whereby rotation of the casing on said member causes said weights to move radially outwardly centrifugally While said abrasive elements move radially inwardly to abrade said member, said supports being counterlevers having generally triangular form, said shafts being located near apices of said counterlevers, said weights being located near ends of longer edges of the counterlevers and said abrasive elements being located near ends of shorter edges of the counterlevers, the other end plate, other annular plate and one of the counterlevers of each of said assemblies being removable to free said abrasive elements for replacing the same, each of said abrasive elements having polygonal ends fitting into correspondingly shaped apertures in said supports, whereby the abrasive elements may be selectively mounted in said supports in different angularly rotated positions.

References Cited in the file of this patent UNITED STATES PATENTS 1,881,441 Fisher Oct. 11, 1932 2,635,393 Barth Apr. 21, 1953 FOREIGN PATENTS 770,158 Great Britain Mar. 20, 1957 

